Our aim was to quantify circulating B cell subsets; immature/transitional, naïve, CD27^- and CD27⁺ memory cells and plasmablasts, in relapsing-remitting multiple sclerosis patients treated with IFN-β. The most relevant findings were a significant increase of plasmablasts and a decrease of immature/transitional B cells, resulting in a decreased ratio between those cells in relapse RRMS, together with an increase of CD27^- and CD27⁺IgM⁺ memory B cell subsets in both phases of the disease. These alterations point to an active B cell response, particularly in relapse, and the above referred ratio could constitute a good biomarker of relapse in patients that underwent IFN-β treatment.

Introduction: Patients undergoing hemodialysis (HD) often exhibit an impaired cellular immune response, which may contribute to an increased susceptibility to infections and other complications. Th1 cells, a subset of T-helper cells, play a crucial role in cellular immunity. However, the modulation of Th1 cells by HD treatment remains unclear. Objective: This study aims to investigate the levels of circulating T cells, especially Th1 cells, and the neutrophil-to-lymphocyte ratio (NLR) in HD patients. Methods: We recruited 26 HD patients and 10 healthy volunteers. Demographical data were collected, and peripheral blood samples were analyzed. Absolute blood cell counts were determined, and T-cell populations were identified using flow cytometry. Th1 cells were defined as IFN-γ-producing CD4⁺ T cells after in vitro activation, and NLR was calculated through the ratio between the neutrophil and lymphocyte counts measured in peripheral blood. Results: We have observed a significant decrease in Th1 subpopulation frequency in HD patients, as well as significant correlations between immunological and demographic parameters, among which are the NLR values and the absolute values of T-cell subsets. Conclusions: These results seem to clarify the role of Th1 cells in modulating the immune responses of hemodialysis-treated patients, potentially considering its frequency as an indicator for CKD development.

Multiple sclerosis is a relapsing and eventually progressive disorder of the central nervous system that continues to challenge researchers who try to understand the pathogenesis of the disease and prevent its progression. Interferon-beta is the most widely prescribed treatment for MS. Peripheral blood seems to mirror the immunological disturbances that underlie MS, which could represent the migration patterns between periphery and other tissues according to the clinical phase of the disease. Based on this assumption, several studies point to significant alterations in peripheral blood homeostasis of different subpopulations of T cells, like γδ T cells or Th1, Th2 and Th17 functional subsets; of B cells subpopulations; and of innate cells like monocytes and dendritic cells. The main goal of this chapter is to make an in-depth review of the major findings described in the literature that correlate specific alterations on different leukocytes subpopulations with disease status, and which therefore have the potential to constitute a peripheral biomarker of disease progression.